Finding equation of normal to a curve.
Well I got this question:
Differentiate from first principals (i did it)
Find the equation of the normal to the curve at point where x = 3.
So first I found y. That means we got
Then I subbed 3 into to get the gradient of the tangent. Answer is
Since the normal and tangent are perpendicular the formula is So that makes
Then I subbed it into
Finally I get
but for some reason the answers in the book says it's different :(
Did I do anything wrong?
Also, I need help with another question:
If find the derivative and find the values of y when
How would I go about starting this one?